Return tubular boiler



` ERNEST VON DER LIPPE.

RETURN TUBULAR BOILER. APPLICATION FILED Nov. 4, 191s.

Patented Nov. 30, 1920.

2 SHEETS--SHEET I- INVENTOR:

I BY '//v l M/ ATTORNEY A EOefkyano/ef aff/1% ERNEST VON DER LIPPE.

RETURN TUBULAR BOILER.

APPLICATION FILED NOV. 4, 1916.

Patented Nov. 30

2 SHEETS-SHEE I N VEN TOR Lw EknBf van Je',

ATTORNEY.. I

UNITED STATES PATENT OFFICE.

lERNES'J? VON DER LIPPE, OF CHICAGO, .'VILLINOIS.

RETURN TUBULAR BOILER.

Specification of Letters Patent. Patnted 'NV 30, 1920 Application ledNovember 4, 1916. Serial No. 129,432.

To all whom. t may concern:

Be it known that I, ERNEST voN DER LIPPE, citizen of the United States,residing at Chicago, in the county of Cook and State of Illinois, have.invented certain new and useful improvements in Return Tubular Boilers;and l do hereby declare the following to be a full, clear, and exactdescription of the invention, such as will enable others skilled in theart to which it appertains to make and use the same.

ln its general aspects, my invention relates to fluid-heating appliancesof the general class including boilers, hot water heaters and hot airfurnaces, its general aims being to .produce a simple, compact andeasily controlled heating appliance which will be unusually eilhcientand which will be practically smokeless even with cheap grades of fuel.For this purpose, my invention aims to produce a heating appliance whichwill permit of a quick starting of the chimney draft, which will utilizethe waste heat of the combustion gases for heating the air supply of thelire box, which will enable this heated air supply to be usedeffectively both above and below the grate, and in which both thechimney or smoke pipe connections and the air supply may be elfectivelyand simultaneously controlled. More particularly, my invention aims toprovide a heating appliance of the class described having upwardlydirected tubes. leading from the lirebox to a combustion chamber, andalso having auxiliary tubes extending downwardly from the combustionchamber and connected toa smoke pipe, to provide means for shuntingvthese auxiliary tubes while the fire is being started or forced, toutilize the heat of the gases after leaving the auxiliary tubes forheating the air supply of the firebox, to provide means for conveyingthis preheated air supply to desirable entrance points located bothabove and below the grate, and means for simultaneously controlling theair supply connections of the ash-pit with both the preheating chamberand the outer air; and to provide a construction which vwill readilyenable the baffle-plate or smoke-plate and the hot air supply tubes tobe replaced. Further objects will appear hereafter.`

While my invention may be employed advantageously with boilers and hotair furnaces of widely varying types, it is particularly adapted for usein connection with a opposite sides of a partition 6 which extendsvvertically downward from the lowerfr plate shown in the diagram of Fig.4, thus shuthouse-warming appliance andis shown in such an embodiment inthe accompanying drawings, in Which- Figure 1 isa central verticalsection through a boiler embodying my invention.

Fig. 2 is a horizontal section, taken along the line 22 of Fig. 1.

Fig. 3 is a fragmentary horizontal section, taken along the line `3 3 ofFig. 1.

Fig. 4 is a vertical diagrammatic view corresponding to Fig. 1 andalsofshowing the simultaneously operable dampers controlling theconnections to the smoke pipe and the air supply.

In the drawings, an outer cylindrical shell 1 houses an upper plate 2and a lower plate 3 connected by vertical tubes 4 and 5, these tubesbeing disposed respectively on and which partition forms a bac-k forboth the i'irebox 7 and the ash-pit 8. All of the said tubes open at thetop into a combustion chamber 9 which is connected to the smoke pipe 10by a flue 11 controlled by a damper 12. The lower ends of the rear tubes5 lead to a Vsmoke chamber 13 which is connected to the smoke pipe 1()by a flue 14 controlled by a damper 15. This smoke chamber is separatedby an inclined smoke-plate or baffle plate 16 from the air-preheatingchamber 2G which adjoins the partition 6, the plate 16 being preferablymadeof a good conductor of heat, such as iron. The upper part of thepartition 6 has a number of perforations, each of which preferably leadsto la short tube 17 projecting into the fire-box and adapted to have therear end of an airinlet tube 23slipped over it. Below the grate 1S, thepartition 6, may also have an opening 19 controlled by va door 20 andconnecting the ashpit 8 with the air-preheating chamber 26. Other doors21 and 22 control openings leading from the outer air to` theair-preheating chamber 26 and the ashpit respectively, and both of thesedoors may v advantageously be controlled simultaneously with the dampers12 and 15 by means of a suitable connecting mechanism, such as the belt24: shown in the diagram of Fig. 4.

In starting the heating appliance of the drawings, the various doors anddampers are turned at right angles to the position ting oli both thelower smoke pipe connection and the air inlet 21. The air supply thenenters through the opening 22 of the ashpit and passes through the grate18, while the Vsmoke and other products of combustion pass upwardthrough the tubes 4 into the combustion chamber 9 Aand thence throughthe flue 11to theA smoke pipe 10, soV

that there is a quite direct passage from the outei' Yair to thechimney.V` When the fire is well started, thereby also warming thechimney and starting astrong draft in the latter, the closure elementsare moved to the position shown in Fig. 4. This change closes the directair-inlet 22 to the yfirebox, but

opens the rear air inlet' 21, Vso that the air mustV pass'tlirough thepreheating chamber 26 before it can reach the fuel either through theashpit or through the tubes 231 Likewise, this Vchange closes the directlconnection from the combustion chamber to the chimney, but openstheconnection through tlie flue 14 to the lower end of the smoke pipe,so'that the gases in the' combustion.

' chamber can reach the smoke pipe by first passing through the returntubes 5, after which they impinge more or less against the baffle plate1G, thus conveying Ysome of their Y heat to the air in the preheatingchamber.

By manipulating the intermediate door 20, the proportion of air suppliedrespectively above and below the grate may be varied according to thenature and' quantity of the lfuel, and in any case the supplying ofprevioiisly heated Vair above the grate through [the tubes 23 (whichtubes preferably have theirfree ends bent downwardly as shownV Y inFig. 1) makes( it easy to secure practically smokeless combustion evenwhen using a cheap grade-of fuel. Besides, the warming of the air supplyby conduction both from the baffie plate and from the partition 6permits of a saving in fuel, so that the heating V'z ipi'iliance ofV Vmyinvention permits of both smokeless and economical operation with ver flittle attention.

I owever, while I have shown an embodia vertical partition and having abody of water 28 as the fluid heated by thertubesi Vand 5, VI do notwish to be limitedto these or other details ofthe construction andarrangement herein disclosed, it being-obvious that the same might bemodified in Vmany ways without departing from the spirit of myinventioni Thus, it willbe evident that the relative size and number ofthe tubes in these ducts Ll:Y and-5 nia-y be varied considerably, aslong as these tubes with the 'connecting chamber 9 formabifurcatedpassage inV below the boiler and each having some of theY Ysaid tubes opening into the said fire box and -inent Vhavingtwo airtubes 23 supported by rear chamber respectively, a vertical partitionbetween the fire-box` and the rear chamber, an upper chamber connectedto the upper ends of all flues, a chimney connected both tothe'upperchamber and to the rear chamber, a 'heat-'conducting partition extendingacrossY the rear chamber, flue coiinections to the chimney, anV airintake for the portion, of thev rear chamber below the last namedpartition, and an air duct conchan'iber with the fire-box and openingabove the grate in the latter. Y' l Y f Signed at Chicago, Illinois,November f 2nd, 1916. y Y

Y Y ERNEST VO'N DER LIPPE.-V

V necting the last named portion of vthe rear

